Drag down from the top of the screen.
This shows you a fast access bar with the time, battery, signal meter on it.
Now drag down from the top again, I drag all the way down the screen, and you'll see the option at the bottom of the list is the ...

Well, I must be the luckiest Pixi 4 owner in the world lol. Mine is being one of the best phones I've had, and I run my own business supplying I. T. stuff so I can choose any I'd like, and I get to play/test dozens each month.
Mine is the 16Gb ...